The head of safety enforcement for the California Public Utilities Commission denied Tuesday that he had threatened state attorneys in a dispute over whether to fine Pacific Gas and Electric Co. for the San Bruno disaster and said he is entitled to carry a gun in the agency's offices - though he said he hadn't done so recently.

Jack Hagan acknowledged that the exchange with the attorneys had become heated. But he described himself simply as "an exasperated client" who was trying to get his attorneys to help him make a case that the money PG&E is spending to improve its natural-gas transmission system is sufficient penalty for the 2010 pipeline explosion that killed eight people.

Hagan also confirmed that he had packed a concealed gun in the commission's San Francisco offices since becoming head of the safety division in 2012, but that he had stopped doing so several months ago after a staffer complained of feeling uncomfortable.

Several of the attorneys who had been working on the regulatory case against PG&E raised Hagan's conduct as an issue in confidential e-mails to their boss, which The Chronicle obtained from a third party this week.

Angry meeting

The attorneys have maintained that PG&E should be fined as much as $2.25 billion for the San Bruno blast and for failing to maintain a safe natural-gas system. When Hagan demanded at a May 31 meeting that they help him build his case that the utility's gas-system spending should suffice, they wrote, they objected and asked him where he had obtained information about some of PG&E's expenditures.

According to one of the lawyers, Hagan replied that the information came from "some fairies. ... I don't have to tell you." He added that they should accept the data "or else," wrote commission attorney Patrick Berdge.

In an interview Tuesday, Hagan would not address the issue of how he came up with the disputed spending totals, citing attorney-client privilege.

"We're not focusing on the right thing - the victims of San Bruno, settling this case and increasing the safety of the pipelines," Hagan said.

He said the work done by the attorneys, who have since been taken off the PG&E case, was "stupendous."

"In the end, they made me a recommendation of what to do and I chose not to follow it. They disagreed. I'm the client - they are the attorneys that work for the client."

He acknowledged that the dispute had been angry. "It was an exasperated client just trying to get what he wanted done in a short amount of time," Hagan said.

In his e-mail to his boss, commission general counsel Frank Lindh, Berdge wrote that Hagan's "angry demeanor ... must be placed in the context of (his) past habit of carrying a concealed gun and knife on his person while at the commission."

Another attorney, Robert Cagen, told Lindh in an e-mail, "I don't have any intention to be in the same room as Hagan, regardless of whether he is unarmed at the time."

Retired peace officer

Hagan, a former special agent with the state Department of Justice, said his status as a retired peace officer allowed him to carry a concealed weapon and that he had done so at the commission offices.

However, he said, "when one of the staff came forward and they were uncomfortable with it, I quit doing that months ago."

He added, "As far as being threatened, I never threatened anybody. There was a discussion."

Lindh and Hagan have said the lawyers asked to be reassigned from the PG&E case, something the lead attorney, Harvey Morris, angrily disputed in an e-mail to Lindh.

The commission's internal dispute prompted the city of San Bruno to ask federal officials Tuesday to assume control over natural-gas regulation in California away from the utilities commission.

"Highly regarded career professionals" in the agency are "fed up with the cozy relationship and conflicts of interest between the commission's leadership and PG&E," city officials wrote.

Hagan said he hadn't seen the letter or heard about it, but added, "Why would (federal pipeline officials) want to decertify us and make us more unsafe?"

San Bruno officials also zeroed in on Hagan's reference to having been advised by "fairies," asking the commission to hand over documents that went into the safety division chief's recommendation that PG&E not be fined.

Who are 'fairies'?

"We demand to know who the 'fairies' are, their identities, and any telephone, e-mail, or other records that shed light on who really directed Hagan's recommendation not to fine PG&E," Mayor Jim Ruane said in a statement.

State Sen. Jerry Hill, D-San Mateo, whose district includes the devastated San Bruno neighborhood, called for the state attorney general to investigate the reassignment of the PG&E case attorneys and whether there was workplace intimidation at the commission.

Hill said it is ironic that employees who work for the head of the safety division "don't feel safe around his presence."